fix: invalid content type format exception

Author: tnc1997

src/AzureAppConfigurationEmulator/ConfigurationSettings/ConfigurationSettingFactory.cs

@@ -2,6 +2,7 @@
 using System.Security.Cryptography;
 using System.Text;
 using AzureAppConfigurationEmulator.Common;
+using OpenTelemetry.Trace;
 
 namespace AzureAppConfigurationEmulator.ConfigurationSettings;
 
@@ -41,11 +42,21 @@ public ConfigurationSetting Create(
         string? value = null,
         IDictionary<string, string>? tags = null)
     {
+        using var activity = Telemetry.ActivitySource.StartActivity($"{nameof(ConfigurationSettingFactory)}.{nameof(Create)}");
+        activity?.SetTag(Telemetry.ConfigurationSettingEtag, etag);
+        activity?.SetTag(Telemetry.ConfigurationSettingKey, key);
+        activity?.SetTag(Telemetry.ConfigurationSettingLabel, label);
+        activity?.SetTag(Telemetry.ConfigurationSettingContentType, contentType);
+        activity?.SetTag(Telemetry.ConfigurationSettingValue, value);
+        activity?.SetTag(Telemetry.ConfigurationSettingLastModified, lastModified);
+        activity?.SetTag(Telemetry.ConfigurationSettingLocked, locked);
+
         if (!string.IsNullOrEmpty(contentType) && !string.IsNullOrEmpty(value))
         {
-            switch (new ContentType(contentType).MediaType)
+            try
             {
-                case MediaType.FeatureFlag:
+                if (new ContentType(contentType).MediaType is MediaType.FeatureFlag)
+                {
                     return new FeatureFlagConfigurationSetting(
                         etag,
                         key,
@@ -55,6 +66,11 @@ public ConfigurationSetting Create(
                         label,
                         contentType,
                         tags);
+                }
+            }
+            catch (Exception e)
+            {
+                activity?.RecordException(e);
             }
         }
 

tests/AzureAppConfigurationEmulator.Tests/ConfigurationSettings/ConfigurationSettingFactoryTests.cs

@@ -0,0 +1,35 @@
+using AzureAppConfigurationEmulator.ConfigurationSettings;
+using NUnit.Framework;
+
+namespace AzureAppConfigurationEmulator.Tests.ConfigurationSettings;
+
+public class ConfigurationSettingFactoryTests
+{
+    private ConfigurationSettingFactory Factory { get; set; }
+
+    [SetUp]
+    public void SetUp()
+    {
+        Factory = new ConfigurationSettingFactory();
+    }
+
+    [TestCase("application/json", typeof(ConfigurationSetting))]
+    [TestCase("application/json;charset=utf-8", typeof(ConfigurationSetting))]
+    [TestCase("application/vnd.microsoft.appconfig.ff+json", typeof(FeatureFlagConfigurationSetting))]
+    [TestCase("application/vnd.microsoft.appconfig.ff+json;charset=utf-8", typeof(FeatureFlagConfigurationSetting))]
+    [TestCase("Invalid.Content.Type", typeof(ConfigurationSetting))]
+    [TestCase(null, typeof(ConfigurationSetting))]
+    public void Create_ConfigurationSetting_ContentType(string? contentType, Type expected)
+    {
+        // Arrange
+        const string key = "TestKey";
+        const string label = "TestLabel";
+        const string value = "{\"id\":\"TestId\",\"enabled\":true}";
+
+        // Act
+        var setting = Factory.Create(key, label, contentType, value);
+
+        // Assert
+        Assert.That(setting, Is.TypeOf(expected));
+    }
+}